Two miles southeast of London's Cheesegrater tower, which sold last month for a record price, there's proof that all is not calm in the city's property market.

At Canada Water, developer British Land Co., which also owned half of the skyscraper, has seen the value of land slashed by almost 11pc as investors lose their appetite for riskier assets. That contrasts with the best properties, which continue to draw buyers

"Prime London assets such as the Cheesegrater with long dated-income have traded at record prices whereas assets facing short-term expiries have suffered," said Sue Munden, a real estate analyst with Bloomberg Intelligence. "Developments were marked down after Brexit as valuers expected investors to require a higher return given the economic uncertainty."

London's commercial property market is in flux with the value of office buildings in the main financial district rising even as rents fall. A wave of Asian buyers have been pouring into the UK capital on the back of the weaker pound following the Brexit vote, snapping up buildings with long leases that offer better returns than government bonds.

That pushed yields for the best offices in the City of London down to 4pc in the first quarter, according to broker Savills Plc, despite doubts about London's economic prospects causing the value of older buildings to decline.

London faces possible job losses to rival European capitals as businesses seek to maintain access to the world's largest market in the wake of the UK's decision to leave the European Union. That increases the risk of a drop in rents and values as the uncertainty created by the two years it will take to negotiate the terms of the country's exit causes companies including GAM Holding AG to delay decisions about leasing new headquarters.

The uncertain outlook has yet to affect the value of the city's modern towers.

Hong Kong real estate investor CC Land Holdings paid £1.15bn (€1.31bn) to buy the Leadenhall Building, as the Cheesegrater is known. The price was "unprecedented" for a skyscraper there on a square-foot basis, Morgan Stanley analyst Bart Gysens said in a March 1 note to clients.

That has encouraged other owners to weigh sales of stakes in trophy buildings, with some owners including Morgan Stanley's real estate investing unit seeking a buyer for stakes in the tower known as The Walkie Talkie.

Many of the investors seeking the best properties are from China via Hong Kong, Courtauld said.

There's about £39.5bn (€45.25bn) of capital targeting London commercial real estate, according to a Great Portland Estates presentation.

Asian investors "are not so bothered about prospective growth as we are," he said.

"If you have got billions tied up in risky assets in your home territory and political risk is elevated, then the prospect of a nice little building in London could be quite attractive whatever the rental growth in the next two years throws up."